MAXIMIZATION OF CHATTER-FREE MATERIAL REMOVAL RATE IN END MILLING USING ANALYTICAL METHODS

ABSTRACT Chatter vibrations in milling, which develop due to dynamic interactions between the cutting tool and the workpiece, result in reduced productivity and part quality. Various numerical and analytical stability models have been considered in the previous publications, where mostly the stability limit of axial depth of cut is emphasized for chatter-free cutting. In this paper an analytical stability model is used, and a simple algorithm to determine the stability limit of radial depth of cut is presented. It is shown that, for the maximization of chatter-free material removal rate, radial depth of cut is of equal importance with the former. A method is proposed to determine the optimal combination of depths of cut, so that chatter-free material removal rate is maximized. The application of the method is demonstrated on a pocketing example where significant reduction in the machining time is obtained using the optimal parameters. The procedure can easily be integrated to a CAD/CAM or virtual machining environment in order to identify the optimal milling conditions automatically.

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